646979803 has 2 divisors, whose sum is σ = 646979804. Its totient is φ = 646979802.

The previous prime is 646979797. The next prime is 646979813. The reversal of 646979803 is 308979646.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 646979803 - 2¹⁷ = 646848731 is a prime.

It is not a weakly prime, because it can be changed into another prime (646979813) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 323489901 + 323489902.

It is an arithmetic number, because the mean of its divisors is an integer number (323489902).

Almost surely, 2^646979803 is an apocalyptic number.

646979803 is a deficient number, since it is larger than the sum of its proper divisors (1).

646979803 is an equidigital number, since it uses as much as digits as its factorization.

646979803 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1959552, while the sum is 52.

The square root of 646979803 is about 25435.7976678539. The cubic root of 646979803 is about 864.8953744283.

The spelling of 646979803 in words is "six hundred forty-six million, nine hundred seventy-nine thousand, eight hundred three".